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	hartrees
Energy at 0K	-153.373536
Energy at 298.15K	-153.372654
HF Energy	-153.373536
Nuclear repulsion energy

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	Σ_g	3441	3373	0.00
2	Σ_g	2234	2190	0.00
3	Σ_g	916	898	0.00
4	Σ_u	3444	3376	143.28
5	Σ_u	2066	2025	1.68
6	Π_g	644	631	0.00
6	Π_g	644	631	0.00
7	Π_g	557	546	0.00
7	Π_g	557	546	0.00
8	Π_u	516	506	95.85
8	Π_u	516	506	95.85
9	Π_u	255	250	3.36
9	Π_u	255	250	3.36

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.683
C2	0.000	0.000	-0.683
C3	0.000	0.000	1.905
C4	0.000	0.000	-1.905
H5	0.000	0.000	2.975
H6	0.000	0.000	-2.975

	C1	C2	C3	C4	H5	H6
C1		1.3655	1.2223	2.5879	2.2925	3.6580
C2	1.3655		2.5879	1.2223	3.6580	2.2925
C3	1.2223	2.5879		3.8102	1.0701	4.8803
C4	2.5879	1.2223	3.8102		4.8803	1.0701
H5	2.2925	3.6580	1.0701	4.8803		5.9505
H6	3.6580	2.2925	4.8803	1.0701	5.9505

atom1	atom2	atom3	angle		atom1	atom2	atom3	angle
C1	C2	C4	180.000		C1	C3	H5	180.000
C2	C1	C3	180.000		C2	C4	H6	180.000

All results from a given calculation for C₄H₂ (Diacetylene)

using model chemistry: B97D3/6-31G*

States and conformations

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Number	Element	Mulliken
1	C	0.659
2	C	0.659
3	C	-0.886
4	C	-0.886
5	H	0.227
6	H	0.227

<r²>	79.060
(<r²>)^1/2	8.892

All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: B97D3/6-31G*

States and conformations

All results from a given calculation for C₄H₂ (Diacetylene)